The 3V pin is the output of the regulator. If you are directly applying power there, then you are bypassing the voltage regulator and disabling/enabling it has essentially no effect on anything downstream. The 3V rail (vreg output) is directly connected to other items on the board.https://learn.adafruit.com/adafruit-huz ... -print-7-2

adafruit_support_carter wrote:The 3V pin is the output of the regulator. If you are directly applying power there, then you are bypassing the voltage regulator and disabling/enabling it has essentially no effect on anything downstream. The 3V rail (vreg output) is directly connected to other items on the board.

Won't the usb-serial chip feed off of this 3V too, though? That's what I'm looking to disable, to minimize power use.

adafruit_support_carter wrote:Why are you not using the BAT pin?

I did try using the BAT pin, but the board would not start. I'm feeding it ~3V from a li-ion battery, and the only way I could seem to get it up was through feeding directly into the 3V rail. I'm still seeing the battery drain awfully quickly, though.

Is there a current writeup or guide to how to minimize power use to the Huzzah32?

There's no way to selectively power the CP2104 and the ESP32. They are both powered by the 3V rail. And sorry, we don't have a guide on this. In addition to hardware considerations, there would also be some software aspects. Like possibly putting the ESP32 into sleep mode, waking up from it, etc.